Biological sciences

Two kinds of quantitative traits (body size and thoracic bristle number) in the South American population of Zaprionus indianus were analyzed and the results were compared to those of ancestral population in the Old World. All American samples were remarkable by their big size, suggesting that they came from a high-latitude African country and the colonizing propagule introduced to Brazil had a fairly large size, preventing any bottleneck effect being detected.

Genetic architecture of wing morpholology in Drosophila simulans and an analysis of temperature effects on genetic parameter estimates

Article Abstract:

The Drosophila wing is used as a model to investigate the mechanisms responsible for size and shape changes in nature, since such changes might underlie morphological evolution. Temperature, sex and line significantly affected wing trait variation, which was mainly characterized by longer wings having the second, fourth and fifth longitudinal veins closer together at the wing tip.

The article focuses on the research of the reaction norms of Zaprionus indianus different traits in relation to growth temperature. Positive correlations between temperature of maximum values of the three size-related traits, between size and ovarioles, and between ovarioles and sternopleural bristles, are discussed.